The present invention relates to a sliding window structure, and more particularly, a sliding window having an improved air-tight structure and/or an improved heat insulating structure.
The prior art documents of Japanese Utility Model Publication No. HEI 1-11911 and Japanese Utility Model Laid-open Publication No. HEI 3-68279 discloses a sliding window structure in which an indoor side sash or shoji (called hereinbelow sash) is mounted to an indoor side portion of a window frame so as to be slidable or movable in the width direction of the window frame and an outdoor side sash is mounted to an outdoor side portion of the window frame and fixed to the side of one of the vertical frame members of the window frame. In such sliding window structure, it is known that auxiliary upper and lower frame members are attached to outdoor side portions of upper and lower frame members of the window frame on the side of a vertical frame member opposite to the vertical frame member to which the outdoor side sash is fixed, and that an auxiliary vertical frame member is attached to an outdoor side portion of that vertical frame member, so as to improve an air-tight performance. When the indoor side sash is closed, these auxiliary upper, lower and vertical frame members are pressed against the indoor side sash through air-tight members, thereby forming an upper transverse space, a lower transverse space and a vertical space therebetween. The lower transverse space is opened to the outdoors so as to make a pressure in the lower transverse space equal to an atmospheric pressure, thereby improving an air-tight performance.
In such known air-tight structure, it is aimed to achieve an improved air-tightness between the window frame and the indoor side sash, but no attention is paid for improving the air-tightness between the window frame and the outdoor side sash.
In the slinding window structure of the described prior art publications, a window glass constituting the outdoor side sash is supported directly to the upper, lower and one vertical frame members through the air-tight members.
However, there is another type of sliding window structure in which the glass is fitted to an upper frame element, a lower frame element, a window end frame element and a mating frame element which constitute an outdoor side sash, and these frame elements are fixed to the window frame. In this type of sliding window structure, it remains to slove a problem on the air-tightness between the window frame and the outdoor side sash.
From another view point in respect of the sliding window structure, that is, the view point of improving a heat insulating performance, the prior art document of U.S. Pat. No. 4,202,137 discloses a sliding door or window in which a window frame is composed of an upper frame member, a lower frame member and bilateral vertical frame members assembled in a rectangular shape, each of which frame members is formed of a heat insulating frame unit which is formed by connecting an indoor side member and an outdoor side member through a heat insulating member, and an indoor side sash is fitted to the indoor side of the window frame and an outdoor side sash is fitted to the outdoor side of the window frame with the heat insulating members of the window frame being interposed therebetween.
The indoor side upper, lower, end and mating frame elements constituting the indoor side sash are each formed of a heat insulating frame Knit which is formed by connecting an indoor side member and an outdoor side member through a heat insulating member, and the outdoor side upper, lower, end and mating frame elements constituting the outdoor side sash are also each formed of a heat insulating frame unit which is formed by connecting an indoor side member and outdoor side member through a heat insulating member.
According to this heat insulating structure, the heat insulating members of the window frame have the same location in the depth direction of the window frame, thereby forming a continuous heat insulating line in the peripheral direction of the window frame. However, the heat insulating members of the indoor side sash do not have the same location in the depth direction of the indoor side sash, thus not forming a continuous heat insulating line in the peripheral direction of the indoor side sash. Similarly, the insulating members of the outdoor side sash do not have the same location in the depth direction of the outdoor side sash, thus not forming a continuous heat insulating line in the peripheral direction of the outdoor side sash. Furthermore, since the outdoor side sash is mounted to the outdoor side relative to the heat insulating line of the window frame, the mating portions of the indoor side and outdoor side mating frame elements are not sufficiently heat insulated, thus providing a problem.